Study author Stroeve believes that the models underestimate the effect of ocean currents carrying ever warmer water into the Arctic Ocean from the Atlantic and Pacific.
"The models don't handle ocean processes quite so well," she said. "This is playing a larger role than we thought."
Still, she added, all the models make it clear that human-caused emissions of carbon dioxide and other atmosphere-warming gases are a major factor in Arctic melting.
"It is highly unlikely that this is natural variability," she said. "I believe this is happening because of changes in our atmosphere" caused by human activities.
The findings ratchet up concerns for Arctic wildlife and the livelihoods of Arctic residents.
"And the [existing] predictions were worrisome enough," said Walter Oechel of the Global Change Research Group at San Diego State University, who was not involved in the new study.
The finding is simply another indicator that earlier predictions about the impact of global warming weren't overly alarmist, Oechel added.
"What we're finding is that most of the estimates are holding up or occurring at an accelerated rate," he said.
"If any mistakes were made, it's that the estimates were overly conservative."
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